1. Field of the Invention
The present invention relates to a toner for developing an electrostatic charge image.
2. Description of Related Art
A toner for developing an electrostatic charge image (hereinafter, also simply referred to as “toner”) used in electrophotographic image forming is demanded to have reduced thermal energy in fixation for the purposes of an increase in printing speed and saving of energy of an image forming apparatus. In response thereto, a toner with a much better low-temperature fixability is demanded.
With respect to such a toner, for example, a toner is known into which a crystalline polyester having sharp meltability is introduced as a binder resin to thereby regulate a rheological property and control a viscoelastic behavior, thereby allowing the toner to simultaneously satisfy low-temperature fixability, and offset resistance for prevention of a damage to an image due to a conveyance roller or the like (see, e.g., Japanese Patent Application Laid-Open No. 2004-309996).
The toner is also known to, for example, have a predetermined ratio of the viscosity and the elasticity upon solidification after melting, to thereby simultaneously satisfy low-temperature fixability, toner storage stability, and resistance against adhesion in paper ejection. Such a toner dominantly exhibits a restoration behavior like a rubber as a toner that forms an image even in the state where adhesion of paper ejected can occur in fixation. Therefore, adhesion of paper ejected can be suppressed (see, e.g., Japanese Patent Application Laid-Open No. 2013-156522).
While the toner described in Japanese Patent Application Laid-Open No. 2004-309996 has an enhanced solidification speed, the toner may be insufficient in stability of fixation of a printed image, to cause, for example, tucking in the image. In addition, while the toner described in Japanese Patent Application Laid-Open No. 2013-156522 is considered to be effective for suppression of such tucking, the elastic recovery thereof can be strong to make the surface of an image hard, resulting in cracking of the surface of a layer of the toner molten forming an image when the image is smeared, and the portion cracked may be peeled off from the image to thereby result in an insufficient image density.